- cypherpunks-legacy - lists.cpunks.org

OPT: Re: crypto flaw in secure mail standards (fwd)
by Jim Choate 22 Jun '01

22 Jun '01

---------- Forwarded message ---------- Date: Fri, 22 Jun 2001 15:00:33 -0400 From: "Jeffrey I. Schiller" <jis(a)mit.edu> To: Derek Atkins <warlord(a)mit.edu> Cc: Don Davis <dtd(a)world.std.com>, cryptography(a)wasabisystems.com Subject: Re: crypto flaw in secure mail standards In fact there are many applications where the separation of the signing operation from the encryption operation are useful and important. Encryption provides a different service then the underlying signature. It protects the document from being read by unintended recipients. The signature can provide proof later that the sender did in fact sign the message. It is always the case that one must be careful what one writes in e-mail, for once delivered to the recipient, the sender looses control of the document. In fact this threat even exists in paper mail. If Alice sends Bob a "The deal is off" letter, but doesn't mark the letter with enough context, Bob can always physically forward the letter to a third party and claim it is from Alice. I believe it is important that message signatures outlive the message's encryption layer. If I receive a signed/encrypted message. I will loose the ability to decrypt it if I loose my private key (or intentionally destroy it to prevent its future compromise). However if I remove the encryption and store the message signed (perhaps protected by other mechanisms in my mail store), I can always verify the signature as long as I have access to the sender's certificate chain. No secrets have to be saved. Btw. I don't believe S/MIME has timestamps in its signature format. PGP does. PGP also implements a "for her eyes only" feature that only permits an encrypted message to be displayed, but not saved in a file. Now of course a sufficiently clever person can circumvent this protection. I am now wondering how hard it would be to circumvent this feature *and* keep the original message signature (of course if you have the PGP source code, you can do this). However, having said all this, Don has a point. There may be a class of message where you want to prove that you originated it *only to the original sender*. If he has a way to do that, it sounds like a good thing. But there isn't a flaw in secure e-mail, just a missing service. -Jeff --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majordomo(a)wasabisystems.com

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OPT: crypto flaw in secure mail standards (fwd)
by Jim Choate 22 Jun '01

22 Jun '01

---------- Forwarded message ---------- Date: Fri, 22 Jun 2001 10:15:57 -0500 From: Don Davis <dtd(a)world.std.com> To: cryptography(a)wasabisystems.com Subject: crypto flaw in secure mail standards All current secure-mail standards specify, as their "high- security" option, a weak use of the public-key sign and encrypt operations. On Thursday the 28th of this month, I'll present my findings and my proposed repairs of the protocols, at the Usenix Technical Conference here in Boston: http://www.usenix.org/events/usenix01/usenix01.pdf Citation: Don Davis, "Defective Sign & Encrypt in S/MIME, PKCS#7, MOSS, PEM, PGP, and XML." To appear in Proc. Usenix Tech. Conf. 2001, Boston. June 25-30, 2001. A short summary: All current secure-mail standards have a significant cryptographic flaw. There are several standard ways to send and read secure e-mail. The most well-known secure mail systems are PGP and S/MIME. All current public- key-based secure-mail standards have this flaw. Here are some examples of the flaw in action: Suppose Alice and Bob are business partners, and are setting up a deal together. Suppose Alice decides to call off the deal, so she sends Bob a secure-mail message: "The deal is off." Then Bob can get even with Alice: * Bob waits until Alice has a new deal in the works with Charlle; * Bob can abuse the secure e-mail protocol to re-encrypt and resend Alice's message to Charlie; * When Charlie receives Alice's message, he'll believe that the mail-security features guarantee that Alice sent the message to Charlie. * Charlie abandons his deal with Alice. Suppose instead that Alice & Bob are coworkers. Alice uses secure e-mail to send Bob her sensitive company-internal sales plan. Bob decides to get his rival Alice fired: * Bob abuses the secure e-mail protocol to re-encrypt and resend Alice's sales-plan, with her digital signature, to a rival company's salesman Charlie. * Charlie brags openly about getting the sales plan from Alice. When he's accused in court of stealing the plan, Charlie presents Alice's secure e-mail as evidence of his innocence. Surprisingly, standards-compliant secure-mail clients will not detect these attacks. ---------------------------------------------------------- Abstract Simple Sign & Encrypt, by itself, is not very secure. Cryptographers know this well, but application programmers and standards authors still tend to put too much trust in simple Sign-and-Encrypt. In fact, every secure e-mail protocol, old and new, has codified na�ve Sign & Encrypt as acceptable security practice. S/MIME, PKCS#7, PGP, OpenPGP, PEM, and MOSS all suffer from this flaw. Similarly, the secure document protocols PKCS#7, XML- Signature, and XML-Encryption suffer from the same flaw. Na�ve Sign & Encrypt appears only in file-security and mail-security applications, but this narrow scope is becoming more important to the rapidly-growing class of commercial users. With file- and mail-encryption seeing widespread use, and with flawed encryption in play, we can expect widespread exposures. In this paper, we analyze the na�ve Sign & Encrypt flaw, we review the defective sign/encrypt standards, and we describe a comprehensive set of simple repairs. The various repairs all have a common feature: when signing and encryption are combined, the inner crypto layer must somehow depend on the outer layer, so as to reveal any tampering with the outer layer. ---------------------------- Once I've presented the paper, I'll make this link live: http://world.std.com/~dtd/sign_encrypt/sign_encrypt7.ps - don davis, boston http://world.std.com/~dtd - --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majordomo(a)wasabisystems.com -- ____________________________________________________________________ Whereof one cannot speak, thereof one must be silent. Ludwig Wittgenstein The Armadillo Group ,::////;::-. James Choate Austin, Tx /:'///// ``::>/|/ ravage(a)ssz.com www.ssz.com .', |||| `/( e\ 512-451-7087 -====~~mm-'`-```-mm --'- --------------------------------------------------------------------

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Two Countries, One City (A civil libertarian/anarcho-capitalist challenge?)
by Jim Choate 22 Jun '01

22 Jun '01

http://www.time.com/time/covers/1101010611/fcities.html James Choate Product Certification - Operating Systems Staff Engineer 512-436-1062 jchoate(a)tivoli.com

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RE: Louis Cypher <cypherl@hotmail.com>
by Trei, Peter 22 Jun '01

22 Jun '01

> From: Anonymous[SMTP:nobody@mix.winterorbit.com] > > Amusing. > The guy caling himself Louis Cypher is apparently connecting to the > Internet from within Mitre. > X-Originating-IP: [129.83.19.1] > Who have you pissed off, Sunder? > -MW- > Um, probably no one. I was on the cypherpunks list as ptrei(a)mitre.org for many years, as oldtimers on the list will remember. Peter Trei

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I WAS SICK OF BEING FAT!!!!!!!
by estoil0c0＠icytundra.com 22 Jun '01

22 Jun '01

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RE: Critiques of Libertarianism
by Faustine 22 Jun '01

22 Jun '01

On Thu, 21 Jun 2001 a3495(a)cotse.com wrote: > "This diversity of libertarian viewpoints can make it quite difficult to > have a coherent discussion with them, because an argument that is valid for > or against one type of libertarianism may not apply to other types." > > ....you mean you actually have to LISTEN to people before you stick them in > a conceptual box and slap your two-bit pre-made labels on them??? Say it > ain't so!!!! Moron. >And you're proud you don't have to listen to folks before you stick 'em in >a box? Er, you might want to have a look at my old posts to get my thoughts on thar sort of thing. >Bullshit, Libertarians choose to call themselves by that label, >it's a self imposed box. Your criticism is without merit. Or perhaps the >ghost of Wittgenstein will walk through you... You probably have a point if you're talking about the "capital L" fanatic types. Nevertheless, I don't think anyone should be so intellectually lazy and mentally impoverished that they need to rely on labels--self-imposed or otherwise--to have a "coherent" conversation. Maybe the people who do deserve to talk at each other. >Further, you misrepresents what he says. Oh? I fully reserve the right to remain unimpresssed. LOL >Check the archives, various >folks have made the distinctions between the various components of CACL >quite clear, it's why I always make it clear what the particular 'common >character' I am refering to when I 'lump 'em into one box'. I'm guessing this has more to do with the caliber and temperament of people who post to message boards than as something representative of any particular body of academic works, such as it is. Face it: if all you knew about any group of ideas was what you could deduce from Usenet posts, it would be a pretty sorry spectacle indeed. What passes for fascinating debate on message boards is more often than not uninformed bush-league armchair philosophizing, it's that simple. In fact, that's part of the problem right there: people are too busy throwing labels around to really get to the meat of the issues. >It is also clear that a global critique of one 'view' isn't necessarily >applicable to the other. But when is a global critique truly useful and relevant at all? The point I'm trying to make is a little clearer if you substitute a more familiar concept: "What is liberalism?" "What has liberalism meant, historically?" "What does it mean to be 'a liberal' in the United Stated today?" See, not so easy, is it. You can start talking about certain aspects of the term and its usage, but it's certainly not the type of thing you can completely cover and come to terms with in a few posts! No need to try to force something rich, complex and evolving into a brittle "all or nothing" proposition. It's as ridiculous to assume that any one person can "speak for" libertarianism as it is to have a "representative of liberalism". The people who try generally aren't with the time it takes to read them. > In other words, there are a variety of issues with a >concomitent multiplicity of views that get pushed into 'libertarian'. Sure-- as is the case with other general terms like "liberalism" and "conservatism". >His point that this makes it hard to understand the fundamental characters to qualify for 'libertarian' is valid. It also happens to be a valid >critique of its practitioners. This might be an issue for partisans and ideologues, otherwise it's 100% irrelevant. As far as I'm concerned, the real enemy is a mindset which allows you to let a label do your thinking for you. > You can take any philosophical position under the sun and always find > idiots and straw men who "support" it to knock around, why should > libertarianism be any different. There's plenty of room for real debate > here, too bad he's not up for it. Oh well! >>Exactly, and if the philosophy can't stand on it's own two feet despite >>this then it deserves the ignomy it will receive. It's not "a philosophy" any more than liberalism is, and you're confusing the supporters with the ideas themselves again. You want to talk Hayek? Let's talk Hayek. You want to debate Stirner? Jim Bell and AP? Go for it. The fact that there isn't much overlap in no way keeps me from having a meaningful and "coherent" conversation about libertarian ideas with people who happen to agree with parts of them. It's when the discussion degenerates into partisans throwing dogma and generalities at each other that it gets really, really tiresome. I'm certainly no purist, but the fact remains that I'm far more likely to pay attention to critiques of the free market by real economists who actually have a clue as to what they're talking about--like Brad Delong at Berkeley(http://www.j-bradford-delong.net). People on all sides can foam at the mouth all they please, but it won't affect policy and scholarship one way or the other. Which in the long run, is all that matters anyway. ~Faustine. BTW, no hard feelings Jim, I think it's great you're bringing this sort of thing up here. Shaking people out of their complacency is always a good thing.

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Louis Cypher <cypherl@hotmail.com>
by Anonymous 22 Jun '01

22 Jun '01

Amusing. The guy caling himself Louis Cypher is apparently connecting to the Internet from within Mitre. X-Originating-IP: [129.83.19.1] Who have you pissed off, Sunder? -MW-

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Audio one-time pad smart-card?
by A. Melon 22 Jun '01

22 Jun '01

Hold the ComDot card, a new product from Tel Aviv-based ComSense Technologies Ltd., up to your computer's microphone and squeeze the slight bump in its center. Otherwise indistinguishable from a garden-variety credit card, it emits a high-pitched series of noises similar to that of a fax machine or dial-up modem. Because it communicates via sound, the ComDot doesn't require a specialized card reader like other "smart" cards -- only a computer with a sound card and a microphone. It is even designed to work over the telephone. [...] The card transmits an encrypted identifying code via high-frequency sound waves -- a long screech, followed by a lower-pitched warble. The computer then verifies the ID with the ComSense servers; the user enters a PIN (personal identification number) for added security, and the log-in is complete. [...] The ComDot itself consists of a three-year battery, computer processor, two speakers and a small amount of memory. It never emits the exact same tone twice, so even if someone trying to gain unauthorized access to patient files were to record the sound and replay it, they would not succeed. [...] Not only could the ComDot sit inside a fraud-proof, ultra-secure credit or ATM card, but the technology could also be used to validate online commerce transactions. Instead of merely requiring consumers to type in their credit card number, they would squeeze their ComDots, and perhaps enter a PIN. [...] http://www.cnn.com/2001/TECH/ptech/06/22/smart.card.reut/index.html

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Information for NBCi Members about www.nbci.com
by NBCi 22 Jun '01

22 Jun '01

This is an informational mailing regarding NBC Internet, Inc. You have received this e-mail because our records indicate that you are a registered user of www.nbci.com. NBCi is in the process of making certain changes to our portal offering that may affect the way you use the site. We are making these modifications in light of recent changes in the Internet advertising and financial markets. The following questions and answers will provide you with information about the upcoming changes. A. What will happen now? 1. Initially, most of NBCi's current features and services will remain operational with certain exceptions, including the following: - New files will not be able to be uploaded to http://sharehouse.nbci.com; - New pictures will not be able to be uploaded to some NBCi clubs; - The Pogo game section of NBCi has recently been transitioned to http://www.pogo.com/. We anticipate that NBCi members may login to the http://www.pogo.com/ url using an existing account, retaining current ranking and earned points. - On July 6th, Fusion One will discontinue their sync service with the NBCi calendar application. (You will still be able to use Fusion One to synchronize with non-NBCi applications.) 2. The www.nbc.com url will continue to take you directly to programming information about the NBC Television Network. Note: In the coming months, you may see additional changes to the www.nbci.com site. It is our intention to provide you with advance notice of any significant changes to our portal offering. Notice will be sent to the alternate e-mail address currently listed in your NBCi membership information. B. What does this mean to you? 1. Make sure you have a backup of all data stored on www.nbci.com (such as your web site and shared files), as well as on Xoom.com and SNAP.com. Such a backup should be stored on your hard drive, on floppy disks or other web site hosting providers, but not on NBCi. 2. Begin evaluating alternative web site hosting providers. We recommend that you plan to have your site and shared files hosted by a different provider as soon as possible and before July 15th. NBCi has made arrangements with Homestead.com for web page hosting and XDrive.com for file storage to help make the transition a smooth one. - For more information about Homestead.com for your web page hosting needs, visit: http://homesteadannouncements.homestead.com/NBCI.html - For more information about Xdrive.com for your file storage needs, visit: http://plus.xdrive.com/target.html?path=signup.html,aff=nbci061301 3. Copy the contents of your address books (used in Calendar and e-mail applications) onto your hard drive so that you have access to that information when you are not on NBCi. (Again, we expect that your e-mail address will continue to work, but you should make a copy of data such as e-mail addresses and the contents of important e-mails for your records.) 4. Copy the contents of your portfolios, such as the stock names and symbols, purchase dates, amounts, etc., so that you have access to that information when you are not on NBCi. Instructions for copying and printing the contents of your address book and portfolio are published at: http://www.nbci.com/LMOID/resource/0,566,-5687,00.html. C. How can you stay informed? - The contents of this e-mail as well as answers to frequently asked questions will be located at: http://www.nbci.com/LMOID/resource/0,566,-5605,00.html - If you have specific questions about your e-mail account, contact mail.com (a separate company) directly using this form: http://www2.email.com/snap/supportform.jhtml. Note: If you use NBCi through one of our ISP distributors, such as PacBell, Verizon or Prodigy, please contact your ISP directly for additional information. General Disclaimer Please note that pursuant to our terms of service (which can be accessed from www.nbci.com) NBCi has the right to unilaterally stop all service and functionality to our web sites; however, we understand the importance of your information and desire to provide you with sufficient notice to allow you to act accordingly. Nothing contained in this mailing is intended to or shall supercede our terms of service. You can view our full terms of service if you have any questions at: http://www.nbci.com/LMOID/resource/0,566,home-764,00.html?fd.ft.ts.h.s-764. For risks about NBCi's business, see its Form 10-K for the year ended December 31, 2000, as well as its other SEC filings. This email was sent to: cypherpunks(a)toad.com ---------------------------------------------------------------------

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<no subject>
by Pieter Kramer 22 Jun '01

22 Jun '01

hey heres another completely safe hommade bomb thats a little funner heres what you nead 1. a jar with a screw on lid preferably plastic because it dosn't shatter that can hold about a cup of water 2. a small container that can hold three or four tabelspoons of water a film canaster will do fine 3. baking soda 4. vinager 5. water baloon 6. nail (optional) 7. dish soap or bubble bath whatever you got that makes bubbles heres how you do it 1.fill the film container with baking soda but not all the way 2. film the plastic jar with vinager and about some dish soap but no all the way to the top (about four tabelspoons will do it for dish soap but other stuff may take more or less) 3. take the lid of the plastic container poke a very small hole about the radius of a pencil than put the water baloon in it and glue it in good on both sides I suggest a glue gun or wood glue not whight school glue 4. heres the trickey part put the film container in the jar so that it floats you may have to take some baking soda out 5. screw the lid on tight 6. now you nead to be carefull not to tip or bump it at all when you are ready when you are shake it this makes the vinager and baking soda combine making the baloon expand and popping spraying foam everywhere 7. if the baloon doesn't explode look inside if their is lots of vinager left you nead more baking soda if their is lots of baking soda left you nead more vinager 8. if you still cant get it to xplodde glue a nail so it will poke the baloon when the baloon expands WARNING be carefull not to get the foam in youre eyes its vinager so it will sting

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